navigation drawer improvement.

lib/ui/common_appbar.dart

@@ -217,30 +217,34 @@ class _CommonAppbarState extends State<CommonAppbar> {
                     itemCount: navigationList.length,
                     itemBuilder: (context, index) {
                       String icon = "assets/icons/${navigationList[index].mobileFontIcon}.svg";
-                        if (navigationList[index].parentId == 1) {
-                          return myListItem(icon, navigationList[index].navigationText, navigationList[index].orderNo == 1 ? true : false, onTap: () {
+                      var subList = navigationList.where((element) => element.parentId == navigationList[index].navigationId).toList();
+                      return Column(
+                        mainAxisSize: MainAxisSize.min,
+                        children: [
+                          if (navigationList[index].parentId == 1)
+                            myListItem(icon, navigationList[index].navigationText, navigationList[index].orderNo == 1 ? true : false, onTap: () {
                               String url = navigationList[index]?.mobileNavigationUrl ?? "";
                               if (url.isEmpty || url.length < 2) {
                                 return;
                               }
                               Navigator.pushNamed(context, url, arguments: null);
-                          });
-                        } else {
-                          return Container(
+                            }),
+                          for (var subItem in subList)
+                            Container(
                               width: double.infinity,
                               child: Row(
                                 children: [
                                   Expanded(
-                                  child: myListItem(icon, navigationList[index].navigationText, false, onTap: () {
-                                    String url = navigationList[index]?.mobileNavigationUrl ?? "";
+                                    child: myListItem("assets/icons/${subItem.mobileFontIcon}.svg", subItem.navigationText, false, onTap: () {
+                                      String url = subItem.mobileNavigationUrl ?? "";
                                       if (url.isEmpty) {
                                         return;
                                       }
                                       var contentId;
-                                    if (navigationList[index].mobileNavigationUrl == "/introduction") {
+                                      if (subItem.mobileNavigationUrl == "/introduction") {
                                         url = ContentInfoScreen.routeName;
                                         contentId = 2;
-                                    } else if (navigationList[index].mobileNavigationUrl == "/encyclopedia") {
+                                      } else if (subItem.mobileNavigationUrl == "/encyclopedia") {
                                         url = ContentInfoScreen.routeName;
                                         contentId = 1;
                                       }
@@ -254,9 +258,11 @@ class _CommonAppbarState extends State<CommonAppbar> {
                                   ),
                                 ],
                               ),
+                            )
+                        ],
                       );
-                        }
-                      })),
+                    }),
+              ),
               Container(
                 margin: EdgeInsets.only(top: 16, bottom: 12),
                 padding: EdgeInsets.only(left: 32, right: 32),
@@ -279,7 +285,7 @@ class _CommonAppbarState extends State<CommonAppbar> {
                       "Powered by Cloud Solutions",
                       maxLines: 1,
                       textAlign: TextAlign.right,
-                        style: TextStyle(fontSize: 14,color: Colors.black87),
+                      style: TextStyle(fontSize: 14, color: Colors.black87),
                     ),
                     SizedBox(width: 8),
                     SvgPicture.asset("assets/logos/cloud_logo.svg", width: 30, height: 30)